Basic ADWR Information

EPA is responsible for safe drinking water, both from your tap and on airplanes. In 2009, EPA published the Aircraft Drinking Water Rule (ADWR) to ensure that safe and reliable drinking water is provided to airline passengers and crew. The ADWR provides additional protection to the public from disease-causing organisms (e.g., pathogens) sometimes found in onboard drinking water by establishing barriers of protection targeted to the air carrier industry.

Prior to publication of the ADWR, EPA placed 45 air carriers under Administrative Orders on Consent (AOCs). Air carriers will remain subject to existing national primary drinking water regulations (NPDWRs) or to existing Administrative Orders on Consent (AOC), where applicable, until the compliance dates specified in the rule are reached.

1. What is the Aircraft Drinking Water Rule (ADWR)?The Aircraft Drinking Water Rule (ADWR) tailors the existing national primary drinking water regulations (NPDWRs) to the unique operating characteristics of aircraft to ensure that safe and reliable drinking water is provided to airline passengers and crew. The rule provides additional protection to the public from disease-causing organisms (e.g., pathogens) sometimes found in onboard drinking water by establishing barriers of protection targeted to the air carrier industry. The ADWR combines sampling, best management practices (e.g., disinfection and flushing of water systems), corrective action, public notification, operator training, and reporting and recordkeeping to improve public health protection while allowing air carriers flexibility in how they achieve these objectives.

2. Why is EPA publishing the ADWR and what concerns does it address?The primary purpose of the ADWR is to ensure that safe and reliable drinking water is provided to aircraft passengers and crew. This entails providing air carriers with a feasible way to comply with the Safe Drinking Water Act (SDWA) and the national primary drinking water regulations (NPDWRs). The existing NPDWRs were designed for traditional, stationary public water systems, not mobile aircraft water systems that are operationally very different. Aircraft must maintain rigorous operating schedules. They fly to multiple destinations throughout the course of any given day and may board drinking water from sources at any of these destinations. Aircraft board water from airport watering points via temporary connections. Aircraft drinking water safety depends on a number of factors including the quality of the water that is boarded from these multiple sources, the care used to board the water, and the operation and maintenance of the onboard water system and the water transfer equipment (such as water cabinets, trucks, carts, and hoses). These unique operational characteristics present different challenges that necessitate tailoring the NPDWRs for aircraft water systems in the final ADWR.

In 2004, EPA found all aircraft water systems to be out of compliance with the NPDWRs. According to the air carriers, it is not feasible for them to comply with all of the monitoring that is required in the existing regulations. Subsequently, EPA tested 327 aircraft of which 15 percent tested positive for total coliform. EPA considers this to be a high percentage of positive samples. In response to these findings, EPA embarked on an accelerated process to tailor the existing regulations for aircraft public water systems. In the interim, EPA placed 45 air carriers under Administrative Orders on Consent (AOCs). Until the final ADWR compliance dates, air carriers remain subject to the existing NPDWRs and AOCs where applicable.

3. Who will be affected by the ADWR?Aircraft which convey passengers in interstate commerce and are public water systems that board only finished water will be affected by this final ADWR. Aircraft that do not provide water for human consumption or those with water systems that do not regularly serve an average of at least twenty-five individuals daily do not meet the definition of a public water system. The final ADWR only addresses aircraft within U.S. jurisdiction.

The ADWR applies to the aircraft’s onboard water system only. The components include: water service panel, storage tanks, pipes, valves, treatment devices, and plumbing fixtures within the aircraft that supply water to passengers or crew. The Food and Drug Administration (FDA) is responsible for regulating the watering points, which include the water cabinets, carts, trucks, and hoses from which aircraft board water. EPA and the states are responsible for regulating the public water systems that supply drinking water to the airport watering points.

5. What is the frequency required for coliform sampling?The frequency of coliform monitoring is based on the frequency of disinfection and flushing of the aircraft water system, as follows:

Routine Disinfection and Flushing and Routine Sample Frequencies

Minimum Routine Disinfection & Flushing Per Aircraft

Minimum Frequency of Routine Samples Per Aircraft

At least 4 times per year = At least once within every three-month period (quarterly)

At least 1 time per year = At least once within every twelve-month period (annually)

At least 3 times per year = At least once within every four-month period

At least 2 times per year = At least once within every six-month period (semi-annually)

At least 2 times per year = At least once within every six-month period (semi-annually)

At least 4 times per year = At least once within every three-month period (quarterly)

At least 1 time per year or less = At least once within every twelve-month period (annually) or less

At least 12 times per year = At least once every month (monthly)

Two coliform samples are taken per monitoring period: One sample must be taken from a lavatory and one sample from a galley. Any total coliform-positive sample must be further analyzed for the presence of E. coli. The air carrier must conduct disinfection and flushing of the aircraft water system in accordance with, or consistent with, the water system manufacturer’s recommendations. This allows for equipment-specific designs and for flexible implementation with the evolution of technology. In cases where a recommended routine disinfection and flushing frequency is not specified by the aircraft water system manufacturer, the air carrier is given the flexibility to choose a disinfection and flushing frequency, and corresponding monitoring frequency, specified in the above table.

Initial Corrective Action and Public Notification Requirements for Aircraft Water Systems*Additional corrective actions based on repeat sample results or follow-up sample results are not reflected in this table.

Monitoring Results or Failure

Corrective Action

Public Notification

If any routine sample is total coliform-positive and E. coli-negative

-- Perform disinfection and flushing no later than 72 hours after being notified by lab of total coliform-positive result, and collect follow-up samples;or-- Restrict public access to the water system no later than 72 hours after being notified by lab of total coliform-positive result; all public access restrictions must remain in-place until the aircraft water system has been disinfected and flushed and a complete set of follow-up samples has been collected;or-- Collect 3 repeat monitoring samples no later than 24 hours after being notified by lab of total coliform-positive result.

If the air carrier chooses to restrict public access to the water system, the air carrier must initiate public notification at that time (i.e., no later than 72 hours after being notified by lab of total coliform-positive result) and continue until the aircraft water system is returned to unrestricted public access.

If any routine sample is E. coli-positive

-- Restrict public access to the water system no later than 24 hours after being notified by lab of E. coli-positive result; all public access restrictions must remain in-place until the aircraft water system has been disinfected and flushed and a complete set of follow-up samples is total coliform-negative;and-- If the aircraft water system cannot be physically disconnected or shut-off, or the flow of water otherwise prevented through the tap(s), the air carrier must disinfect and flush the system no later than 72 hours after the lab notifies the air carrier of the E. coli-positive result;and-- Collect follow-up samples.

Initiate public notification when restriction of public access is initiated (i.e., no later than 24 hours after being notified by lab of E. coli-positive result) and continue until the aircraft water system is returned to unrestricted public access.

Failure to perform routine disinfection and flushing or failure to collect and analyze the required routine coliform samples

Restrict public access to the water system no later than 72 hours after discovery of the failure; all public access restrictions must remain in-place until the aircraft water system has been disinfected and flushed and a complete set of follow-up samples has been collected.

Initiate public notification when restriction of public access is initiated (i.e., no later than 72 hours after discovery of the failure) and continue until the aircraft water system is returned to unrestricted public access.

Failure to collect and analyze the required follow-up samples as a result of an E. coli-positive result

-- Restrict public access to the water system no later than 24 hours after discovery of the failure; all public access restrictions must remain in-place until the aircraft water system has been disinfected and flushed and a complete set of follow-up samples is total coliform-negative;and-- If the aircraft water system cannot be physically disconnected or shut-off, or the flow of water otherwise prevented through the tap(s), the air carrier must disinfect and flush the system no later than 72 hours after the lab notifies the air carrier of the E. coli-positive result;and-- Collect follow-up samples.

Initiate public notification when restriction of public access is initiated (i.e., no later than 24 hours after discovery of the failure) and continue until the aircraft water system is returned to unrestricted public access.

Failure to collect and analyze the required repeat or follow-up samples as a result of a total coliform-positive and E. coli-negative result

Restrict public access to the water system no later than 72 hours after discovery of the failure; all public access restrictions must remain in-place until the aircraft water system has been disinfected and flushed and a complete set of follow-up samples has been collected.

Initiate public notification when restriction of public access is initiated (i.e., no later than 72 hours after discovery of the failure) and continue until the aircraft water system is returned to unrestricted public access.

When the air carrier becomes aware of an E. coli-positive event resulting from:(1) boarding water from a watering point not in accordance with FDA regulations (21 CFR part 1240 subpart E), or

(2) boarding water that does not meet NPDWRs applicable to transient non-community water systems (§§141.62 and 141.63, as applied to TNCWS), or

(3) boarding water that is otherwise determined to be unsafe due to non-compliance with the procedures specified in §141.804(b)(6).

-- Restrict public access to the water system no later than 24 hours after discovery of the failure; all public access restrictions must remain in-place until the aircraft water system has been disinfected and flushed and a complete set of follow-up samples is total coliform-negative;and-- If the aircraft water system cannot be physically disconnected or shut-off, or the flow of water otherwise prevented through the tap(s), the air carrier must disinfect and flush the system no later than 72 hours after the lab notifies the air carrier of the E. coli-positive result;and-- Collect follow-up samples.

Initiate public notification when restriction of public access is initiated (i.e., no later than 24 hours after discovery of the failure) and continue until the aircraft water system is returned to unrestricted public access.

When the air carrier becomes aware of a non-E. coli-positive event resulting from:(1) boarding water from a watering point not in accordance with FDA regulations (21 CFR part 1240 subpart E), or

(2) boarding water that does not meet NPDWRs applicable to transient non-community water systems (§§141.62 and 141.63, as applied to TNCWS), or

(3) boarding water that is otherwise determined to be unsafe due to non-compliance with the procedures specified in §141.804(b)(6).

Restrict public access to the water system no later than 72 hours after discovery of the failure; all public access restrictions must remain in-place until the aircraft water system has been disinfected and flushed and a complete set of follow-up samples has been collected.

Initiate public notification when restriction of public access is initiated (i.e., no later than 72 hours after discovery of the failure) and continue until the aircraft water system is returned to unrestricted public access.

7. What coliform sampling plans and operations and maintenance plans need to be developed?Each air carrier, for each aircraft that it owns or operates, must have a coliform sampling plan and an aircraft water system operation and maintenance plan by April 19, 2011 for each existing aircraft water system, and within the first calendar quarter of initial operation for new aircraft water systems. These plans must be included in a Federal Aviation Administration-accepted aircraft operations and maintenance program.

8. What types of inspections or audits are required by the ADWR?Each air carrier must conduct a self-inspection of each aircraft water system no less frequently than once every 5 calendar years. In addition, EPA may conduct compliance audits as deemed necessary. The air carrier must address significant deficiencies found as a result of routine compliance audits or self-inspections within 90 days of identification of the deficiency, or where such deficiency is identified during extended or heavy maintenance, before the aircraft is put back into service.

9. How will information (inventory data, sampling data, etc.) be transmitted to EPA?Reporting will begin 18 months following publication of the ADWR. As the primacy agency, EPA has oversight responsibility for aircraft water system reporting information. To facilitate collection and analysis of aircraft water system data, EPA is developing an internet-based electronic data collection and management system. This approach is similar to that used under the EPA SDWIS/STATE (Safe Drinking Water Information System/State version) reporting program. If an air carrier determines that it or its laboratory does not have the capability to report data electronically, the air carrier can submit a request to EPA to use an alternate reporting format. Regardless of the reporting process used, air carriers are to report the required information based on the schedule as stipulated in the ADWR.

10. What are the compliance dates in the final ADWR?The first deadline for compliance under ADWR is April 19, 2011, where air carriers must comply with various planning and reporting requirements (e.g., develop operations and maintenance plans, report aircraft inventory) and October 19, 2011, for compliance with other rule requirements (e.g., conduct routine disinfection and flushing, conduct routine monitoring).

11. What are coliforms?Coliforms are a group of closely related bacteria most of which are natural and common inhabitants of the soil and ambient waters (such as lakes and rivers) and in the digestive tracts of humans and other warm-blooded animals.

The presence of total coliform, in and of itself, is not indicative of a health risk. Coliform bacteria will not likely cause illness. However, the presence of coliform bacteria in drinking water indicates that other disease-causing organisms (pathogens) may be present in the water system.

12. What is E. coli?E. coli is a subgroup of the fecal coliform group. It is found in great quantities in the intestines of people and warm-blooded animals. If total coliform is present in a drinking water sample, EPA requires that it also be tested for E. coli.

Most E. coli are harmless. Some strains, however, may cause illness – diarrhea, cramps, nausea, headaches, or other symptoms. The presence of E. coli or fecal coliform in a drinking water sample may indicate human or animal fecal contamination - meaning that pathogens may be present.

13. What are Administrative Orders on Consent (AOCs)?EPA placed 45 air carriers under Administrative Orders on Consent (AOCs). These orders were put in place to protect the traveling public while EPA developed the ADWR. Agency agreements with the air carriers and resulting administrative orders signed by the air carriers will remain in effect until the compliance dates specified in the final rule.

EPA began a review of existing guidance in 2002. In response to aircraft drinking water test results, EPA accelerated efforts to develop regulations for aircraft drinking water. EPA worked collaboratively with other federal agencies overseeing the air carrier industry, industry representatives, and the public to develop the ADWR, published in 2009. Until the compliance date specified in the rule, air carriers remain subject to existing national primary drinking water regulations (NPDWRs) and AOCs where applicable.

14. What do the Administrative Orders on Consent (AOCs) require airlines to do?The Administrative Orders on Consent require the airlines to implement regular monitoring and disinfection protocols for their aircraft for a period of two years from the effective date of the Order and for subsequently negotiated monitoring periods. Specifically, the orders require the air carriers to: perform regular monitoring of aircraft water systems; regularly disinfect aircraft water systems and water transfer equipment; undertake corrective action when there is a total coliform positive sample result; provide public notice when there is a total coliform positive sample result; and supply information regarding various aspects of its water practices.

15. What about international flights?A significant part of aircraft travel includes international flights. These aircraft may board water from foreign sources which are not subject to EPA drinking water standards. The ADWR only addresses aircraft regulated under Safe Drinking Water Act (SDWA). SDWA does not regulate aircraft water systems operating outside the US; however, EPA supported an international effort led by the World Health Organization (WHO) to develop international guidelines for aircraft drinking water.

16. Who regulates water on passenger airplanes in the United States?In the United States, drinking water safety on airlines is jointly regulated by the EPA, the Food and Drug Administration (FDA), and the Federal Aviation Administration (FAA). EPA regulates the public water systems that supply water to the airports and the drinking water once it is onboard the aircraft. FDA has jurisdiction over culinary water (e.g., ice) and the points where aircraft obtain water (e.g., pipes or tankers) at the airport. In addition, air carriers must have FAA-accepted operation and maintenance programs for all aircraft, this includes the potable water system.

17. What should the traveling public do?Passengers with suppressed immune systems or others concerned may wish to request bottled or canned beverages while on the aircraft and refrain from drinking tea or coffee that does not use bottled water. While boiling water for one minute will remove pathogens from drinking water, the water used to prepare coffee and tea aboard a plane is not generally brought to a sufficiently high temperature to guarantee that pathogens are killed.